In some existing protocols, a data frame includes three parts, i.e. a media access control (MAC, Media Access Control) frame header, a frame body (Frame Body) and a 4-byte frame check sequence (FCS, Frame Check Sequence) domain, wherein the MAC frame header includes a 2-byte frame control (FC, Frame Control) field, a 2-byte duration/identifier (Duration/ID) field, an 18-byte address field and a 2-byte sequence control (Sequence Control). In this case, a fixed overhead of a data frame (an MAC frame header and an FCS domain) is as much as 28 bytes. However, a data packet in 802.11ah application scenario is generally quite short, e.g. a shortest data packet in a smartgrid is 25 bytes only. Thus, an MAC frame header has a relatively large overhead.
An existing method for compressing a data frame is to simplify a receiving address (RA) to an association identifier (AID) allocated to an STA by an AP, compute a complete RA address in an FCS field, and employ a partial transmitting address (PTX) to represent a transmitting address (TA).
However, a reception station may not necessarily be a destination station to be reached by a data frame, and a transmission station may not necessarily be a source transmission station of the data frame. In presence of data frame forwarding, transmission cannot be completed in the prior art.
Therefore, it is necessary to provide a method and an apparatus for transmitting a data frame, so as to reduce overhead of a frame header, improve transmission efficiency, and complete transmission in presence of data frame forwarding.